Effects of anemoside B4 on the expression of apoptosis-associated proteins in the retina of diabetic rats / 中华老年医学杂志

ABSTRACT

Objective:To investigate the effects of anemoside B4 on apoptosis of retinal cells in diabetic rats.Methods:Sixty Sprague-Dawley rats were randomized into three groups the normal control(control), diabetic rats(DM)and diabetic rats treated with Anemoside B4(B4)groups(n=20, each group). Rats in the DM and B4 groups were rendered diabetic with an intraperitoneal injection of streptozotocin(STZ, 60 mg/kg). After 3 days of successful modeling, rats in the B4 group were intraperitoneally injected with anemoside B4(5 mg/kg), twice/day, for 8 weeks, while rats in the control and DM groups were injected with an equivalent volume of normal saline.After 8 weeks of anemoside B4 and normal saline injection, rats were sacrificed and retinas were harvested for examination.Paraffin sections of retina were stained with the hematoxylin-eosin(H-E)method for morphological evaluation.Protein levels of Bax and Bcl-2 were detected by using Western blot.The expression of caspase-3 mRNA was detected with quantitative PCR.Results:H-E staining results showed the control group had intact retinal structure and clear morphological features, whereas disordered retinal structure, thinner layers, and sparse and disorganized cells were seen in the DM group.However, retinal structure and morphology were improved after treatment with anemoside B4.Compared with the control group, the protein expression of Bcl-2 was lower( t=57.81, P<0.01), the protein expression of Bax was higher( t=10.47, P<0.01), and the Bcl-2/Bax ratio was lower( t=23.98, P<0.01)in the DM group.Compared with the DM group, the protein expression of Bcl-2 was higher( t=41.07, P<0.01), the protein expression of Bax was lower( t=6.811, P<0.01), and the Bcl-2/Bax ratio was higher( t=14.70, P<0.01)in the B4 group.Caspase-3 mRNA expression was higher in the DM group than in the control group( t=7.916, P<0.01), but was lower in the B4 group compared with the DM group( t=6.221, P<0.01). Conclusions:Anemoside B4 can inhibit the apoptosis of retinal cells by up-regulating Bcl-2 expression and down-regulating Bax and caspase-3 expression in diabetic rats.